In Northern Yellowstone Lake, earthquakes occur at a mean rate of 1.2 quakes per year. Let X be the number of quakes in a given year.
(a) Justify the use of the Poisson model.
(b) What is the probability of fewer than three quakes?
(c) More than five quakes?
(d) Construct the probability distribution (Excel or Appendix B) and make a graph of its PDF.